Geoege westinghouse



(No Model.)

G. WESTINGHOUSE, Jr.

MOUNTING ARMATURES 0F DYNAMOS.

No. 888,679. Patented May 29, 1888.

I I I I .n' a v N PETERS. Pimlz-Lnhogmphur, Washington, 0.1.:

' UNITED STATES PATENT OFFICE.

GEORGE WVESTINGHOUSE, J R., OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THEWESTINGHOUSE ELECTRIC COMPANY, OF SAME PLACE.

MOUNTING ARMATURES OF DYNAMOS.

SPECIFICATION forming part of Letters Patent No. 383,679, dated May 29,1888.

Application filed September 1, 1887. Serial No. 218,463.

To aZZ whom it may concern.-

Be it known that I, GEORGE WESTINGHOUSE, J11, a citizen of the UnitedStates, residing in Pittsburg, in the county of Allegheny, in the Stateof Pennsylvania, have invented certain new and useful Improvements inMounting Armatures for Electric Machines, of which the following is aspecification.

The invention relates to a method of mounting the armatnres of electricmachines so as to relieve the bearings of undue friction.

The invention consists in availing of an excess of attraction which thepoles of a fieldmagnet upon one side of the armature may be caused toexert upon the armature by mounting the armature slightly eccentric withrefer ence to the circle of the field-magnet poles. This may beutilized, for instance, by purposely mounting the armature with its axisof revolution slightly above the axial line of the field-magnet poleswhen it is desired to relieve the bearings from the weight of thearmature, and in case it is desired to compensate for the pull ortension ofthe driving-belt the axisofthe armature may lie in the planeof the resultant force exerted upon the armature and upon the oppositeside of the circle of the field-magnets from the direction of the force.

In the accompanying drawings, Figure 1 is a side elevation of anarmature and a portion of a field-magnet as organized to illustrate theapplication of theinvention when it is desired to overcome the force ofgravity alone. Fig. 2 illustrates the method of acting against the forceof gravity and the tension of the belt.

Referring to Fig. 1, A represents the armature, and B B B the fieldmagnet cores, of an electric machine. The cores are formed in a circle,which is indicated by the dotted line. The armature is mounted insuitable supports, one of which is indicated at C. The axis of thearmature is very slightly raised above the center of the circle 0. Theupward pull eX- erted by the field-magnet upon the armature willtherefore be in excess of the downward pull, and this will compensate ortend to compensate for the force of gravity. In practice (No model.)

it is found that a very slight eccentricity would be sufficient to evenlift the armature from the hearings were the upper portions or caps, D,removed. By properly placing the armature with reference to the strengthof the current employed and the weight of the armature the force withwhich the armature will rest upon the bearings may be made very slight,and the consequent wear correspondingly diminished.

In Fig. 2 the armature A is shown as mounted with its axis slightlytoward the upper lefthand side. In this instance the force of gravity isindicated by dotted line G and the pull of the belt F is indicated bythe dotted line T. The values of the two forces are such that theresultant is in the direction indicated by the dotted line R. Then theaxis of the armature is placed with reference to the center of thecircle 0 in an extension of the plane R beyond the center of the circle0'. XVhen the machine is in operation, therefore, the resultant forcewill be correspondingly counteracted.

I claim as my invention-- 1. In an electric machine, field-magnet polesarranged in a circular series and an armature mounted upon its bearingswith its axis of revolution eccentric with reference to the circle ofthe field-magnet poles, whereby the pressure of the armature upon itsbearings is opposed by the excess of the magnetic attraction exerted bythe nearer poles of the field-magnets.

2. In an electric machine, the combination, with the field-magnet polesarranged in a circular series, of an armature having its axis ofrevolution eccentric with reference to the circle of said poles, beinglocated in a plane constituting a continuation of the plane ofresultantpull of the force of gravity and the tension of the driving-belt of themachine beyond the center of the series of field-magnet poles.

In testimony whereof I have hereunto subscribed my name this 11th day ofJuly, A. D.

GEO. WESTINGHOUSE, JR. Witnesses:

W. D. UPTEGRAFF, CHARLES A. TERRY.

